The present invention relates to a structure of mounting a tire monitoring device on a support core member which enables run-flat traveling. More particularly, the present invention relates to a mounting structure of a tire monitoring device, in which the tire monitoring device is enabled to function as a warning device notifying a limit of run-flat traveling.
In response to demands in the market, numerous techniques have been proposed to allow a vehicle to run in an emergency for a certain distance even when a pneumatic tire is punctured while the vehicle is running. Some of these proposed techniques (such as the one disclosed in Published Japanese Translation of a PCT Application No. 2001-519279) enable run-flat traveling by inserting a hollow-structured support core member into the cavity of a pneumatic tire assembled to a rim, and supporting a flat tire by the support core member.
It is difficult for a driver to have an immediate grasp of puncture conditions in a tire/wheel assembly with a run-flat function. Therefore, a tire monitoring device typified by a pressure warning device is generally provided together with the run-flat function. The tire monitoring device is attached to a rim well or the like and transmits information of the inside of a tire detected by a sensor to a receiver on a vehicle through an antenna (refer to Published Japanese Translation of a PCT Application No. Hei 8-505939, for example).
Nevertheless, although the tire monitoring device effectively functions in assessing the puncture conditions, the information of the inside of the tire, such as air pressure and temperature, does not notify a limit of run-flat traveling. The run-flat traveling limit depends on the damage condition of the pneumatic tire due to friction with the support core member, or the damage condition of the support core member itself. Therefore, a development of a warning device which notifies the limit of run-flat traveling has been required.